1. Field of the Invention
The present invention relates to a semiconductor photoelectric conversion device which has at least one PIN structure in which a first conductivity type (P- or N-type) non-single-crystal semiconductor layer, an intrinsic non-single-crystal semiconductor layer and a second conductivity type (reverse from the first conductivity type) non-single-crystal semiconductor layer are sequentially laminated in that order. Further, the present invention pertains to a method for the manufacture of such a semiconductor photoelectric cnversion device.
2. Description of the Prior Art
Heretofore a variety of semiconductor photoelectric conversion devices have been proposed which are of the type having at least one PIN structure mentioned above.
With these kinds of devices, light incident thereto creates carries, that is, electron-hole pairs in the intrinsic layer and the electrons and holes flow into one of the first and second conductivity type layers, that is, the N-type layer, and into the other, that is, the P-type layer, respectively, developing photo-voltage. Accordingly, in order to obtain a high photoelectric conversion efficiency, it is desired that the intrinsic layer of the PIN structure have no recombination centers with which the carriers combine. To this end, it is the general practice in the prior art to dope the intrinsic layer of the PIN structure with hydrogen or a halogen as a recombination center neutralizer.
Nevertheless, a relatively large number of recombination centers remain unextinguished in the vicinities of the boundaries between the intrinsic layer and the P-type layer and between the intrinsic layer and the N-type layer. These remaining recombination centers inflict losses on the electrons and holes flowing toward the N-type and P-type layers, respectively. Therefore, the prior art devices have the defect of low photoelectric conversion efficiency although the intrinsic layer of the PIN structure is doped with the recombination center neutralizer.